1. Field of Invention
The present disclosure relates to a pixel driving circuit. More particularly, the present disclosure relates to a OLED pixel driving circuit.
2. Description of Related Art
With advances in electronic technology, display panels are widely used in our daily lives, such as being used in mobile phones and computers.
A typical organic light emitting diode display includes a scan circuit, a data circuit, and a pixel array of pixel driving circuits. Each of the pixel driving circuits in the pixel array includes a driving transistor, a switching transistor and an organic light emitting diode. The scan circuit can sequentially generate a plurality of scan signals, and provide the scan signals to scan lines, so as to sequentially turn on the switching transistors of the pixel driving circuits. The data circuit can generate a plurality of data signals and provide the data signals to the driving transistors via the switching transistors which turn on, so as to enable the driving transistors to drive the organic light emitting diodes according to the data signals. With such operation, the organic light emitting diodes in the organic light emitting diode display are able to emit light and display images.
The amperage of the driving current provided to the organic light emitting diode by the driving transistor corresponds to the data signal and the threshold voltage of the driving transistor. However, threshold voltage offsets of the driving transistors in different pixel driving circuits may exist due to different operating conditions and manufacturing processes. These offsets may cause uneven brightness of the organic light emitting diodes, and ultimately result in mura defects.
Thus, an important area of research in this field involves ways in which to overcome such a problem.